1. Field of the Invention
The invention relates to an actuator comprising a metal housing that includes of a plurality of housing parts, an electric motor, an actuating member, a transmission mechanism that adapts the movement of the electric motor to the actuating member, and an electronics system for controlling the electric motor.
Actuators that have an actuating member that is driven by an electric motor and that is provided in the form of a flap or a journal, or are used as actuators or valves in motor vehicles are known. The metal housings used are generally cast aluminum housings, since such housings have sufficient strength and relatively low weight. In order to introduce the components into the housing, said housing consists of two or more housing parts. Since actuators are generally exposed to high temperatures in motor vehicles, the aluminum casing consisting of a plurality of parts is used, on account of its good thermal conductivity, to cool the components arranged in the housing and/or to cool the heat released by the electric motor. With use of the actuator in the high-temperature range, it is also known to provide active cooling in the form of a water-cooling system in the housing. It is disadvantageous that the arrangement of a water-cooling system increases the cost for the aluminum housing significantly. In housings without water-cooling system, the housing parts must have relatively thick walls for sufficient thermal capacity in order to attain effective cooling. Such a housing has a relatively high weight.